Impact of extrusion on the physicochemical parameters of two varieties of corn (<i>Zea mays</i>)

Abstract

Ecuador has a significant genetic diversity of maize, which comes in different shapes, sizes and colors and plays a crucial role in food security. This research aimed to evaluate the physicochemical parameters of the extrusion process of two improved maize varieties (INIAP-176 and INIAP-180). The factors under study were two temperatures (140 ℃ and 150 ℃) and two screw speeds (230 rpm and 280 rpm). The applied extrusion conditions showed significant effects on the nutritional content, functional properties, texture attributes and sensory acceptability. The extruded products presented average values of 2.64% moisture, 0.61% ash, 8.54% protein, 0.61% ether extract, 1.55% crude fiber and 88.70 g/100 g were nitrogen-free extract (NFE) about dry weight of sample. Also, extrusion of the two maize varieties at a temperature of 150 ℃ and a screw speed of 280 rpm recorded high values of the expansion index and low levels of bulk density for functional properties. Instrumental texture analysis determined that the best attributes expressed as hardness, fracturability and adhesiveness in the expanded maize obtained from INIAP-176 at a speed of 280 rpm. The application of extrusion in these improved maize varieties allowed the production of high-quality snacks for the consumer.